Engine temperature guard

ABSTRACT

A device for slowing down or stopping of sparkplug fired internal combustion engines whenever the engine reaches a predetermined temperature to prevent damaging of the engine including means for mounting a heat sensing device upon a selected portion of the engine and providing therein a conductive member being held in a first position by a heat destructable member and shiftable from this position when the heat destructable member has been destroyed to a second conducting position and including a conductive wire extending from the area of contact of the conductive member in its second position to the spark plug such that when the heat destructable holding element is destroyed the circuitry will be completed to short the electrical energy from the distributor to the engine block and thereby bypass the spark plug. An inspection aperture is provided to permit inspection of the unit without total removal from the engine block.

United States Patent Lenz [ Jan. 1, 1974 [5 ENGINE TEMPERATURE GUARD 3,499,130 3/1970 Norred 123/198 1) [75] Inventor: John OJLenz, Coon Rapids, Iowa Przmary Examiner-Al Lawrence Smith [73] Assignee: Havir Manufacturing Company, St. Atm y jame R Cwayna Paul, Mich.

[221 Filed: Oct. 4, 1972 ABSTRACT [21] AppL No: 294 853 A device for slowing down or stopping of sparkplug fired internal combustion engines whenever the engine reaches a predetermined temperature to prevent dam- [52] US. Cl..... 123/198 DC, 123/41.l5, 123/148 S,

ZOO/61.08, 337/407 Int. Cl... F02b 77/00, F02p 11/02, HOlh 37/76 [58] Field of Search 123/198 D, 198 DC, 123/198 F, 148 S, 41.15; 200/6108; 337/407, 408, 409

[56] References Cited UNITED STATES PATENTS 661,736 1l/19OO Freymann 337/409 1,206,564 11/1916 McDonough 337/407 1,833,765 11/1931 Webber et 211v 337/407 2,231,845 2/1944 Curran 123/198 DC 2,442,830 6/1948 Spracher 1 337/409 2,445,625 7/1948 Meinholdt 1 l23/41.15 3,385,940 5/1968 Roper 337/407 X 3,420,217 l/l969 Powell et a1. 337/407 X aging of the engine including means for mounting a heat sensing device upon a selected portion of the engine and providing therein a conductive member being held in a first position by a heat destructable member and shiftable from this position when the heat destructable member has been destroyed to a second conducting position and including a conductive wire extending from the area of contact of the conductive member in its second position to the spark plug such that when the heat destructable holding element is destroyed the circuitry will be completed to short the electrical energy from the distributor to the engine block and thereby bypass the spark plug. An inspection aperture is provided to permit inspection of the unit without total removal from the engine block.

6 Claims, 4 Drawing Figures ENGINE TEMPERATURE GUARD Applicant has provided herein a device designed to protect spark plug fired, internal combustion engines from over heating by providing a simple grounding technique to at least several of the spark plugs which grounding device is operative only after the engine has reached a certain predetermined dangerous temperature.

With applicants device a sensing unit is simply attached to an available portion of the engine block and simply connected to the spark plug such that a grounding circuit is completed after the engine reaches a predetermined dangerous temperature and the lower resistance of this unit as compared to the gap of the sparkplug will cause electrical energy to pass through the guard device and ground to the engine block. With this type of device if all of the cylinders of the engine are so connected obviously all of the spark plugs energy will be grounded and the engine will stop. If the device is only used on selected cylinders then the engine will begin to miss and the user is alerted as to the dangerous heat condition but he may still be able to drive the unit to a safe location for repair or the like.

It is therefore an object of applicants invention to provide a device for spark plug fired, internal engines which will protect and guard against the overheating thereof.

It is a further object of applicants invention to provide a device for grounding out the electrical energy to spark plugs of internal combustion engines when the engine reaches a predetermined dangerous temperature.

It is still a further object of applicants invention to provide a temperature guard for internal combustion engines which includes a closable circuit system actuated by the use of a heat destructable material and having means for visually inspecting the unit to determine the operative condition thereof.

These and other objects and advantages of applicants invention will more fully appear from the following description made in commection with the accompanying drawings in which the same numeral is utilized to identify the same or similar parts throughout the several views, and in which:

FIG. 1 is a perspective illustration of an installation of an engine temperature guard utilizing the concepts of applicants invention;

FIG. 2 is a perspective view of the temperature guard device taken from the bottom end thereof;

FIG. 3 is a vertical section taken substantially along Line 33 of FIG. 1 and illustrating the unit in normal condition when the engine is running below the dangerous temperature; and,

FIG. 4 is a view similar to FIG. 3 illustrating the unit in its second position wherein the grounding circuit is actuated.

In accordance with the accompanying drawings, applicants temperature guard device for use with spark plug fired, internal combustion engines is generally designated l and performs a function to short the electrical energy from spark plugs of all or selected of the cylinders of the engine and this device may be utilized on either water or air cooled engines with certain minimal modifications thereof as will be explained hereinafter.

As illustrated, the unit includes a first housing member 11 of a non-conductive material, having a generally frusto conical shape and having an internal passage 12 extending at least partially from one end of the body 11 to a closed end 13 which closed end likewise has a passage 14 therethrough such that a conductive wire or the like 15 may be inserted therein and captured therein. A first conductively selected and enlarged flange area 16 is provided on conductor 15 and is arranged interiorly of the passage 12 and a sealing material 17 is provided exteriorly of the body 11 to waterproof the conductor 15 to the housing 1 l. The opposite end of this conductor 15 is provided, in the form shown, with a conductive ring member 18 such that the same may be easily placed about the terminal of a spark plug S.

The lower end of the body 11 is provided with a first rasially outwardly extending shoulder 20 upon which a first biasing member 21 is provided. A clamping device generally designated 22 is provided and is arranged for certain limited movement along the periphery of the body 11' and includes a first upper circular portion 23 having an aperture 24 therethrough to permit the same to slide along the body 11 and which is provided with a pair of downwardly directed arm members 25, 26 which arm members terminate in a pair of inwardly directed prong members 27, 28 which as illustrated in FIG. 2 are provided with gripping indentations 29, 30. These arm members 25, 26 brovide a spring loading arrangement for the gripping portions thereof such that the same may be spread apart and placed around the head bolt H of the engine and be secured to the engine without requiring that any modifications be made to the engine and without requiring that the head bolt be loosened.

The operation of the clamping device 22 in conjunction with the spring 21 and the body 11 of the unit 10 should be obvious in that when the clamping device 22 is placed about the head bolt H the spring 21 will normally urge the bottom of the device 10 downwardly against the head bolt. The same spring configuration will permit lateral shifting or tilting of the body 11 sideways from the clamping device such that inspection of the interior thereof may be made without removing the same from the head bolt. In this manner the interior fuse portion designated generally 35 may be removed and replaced if necessary.

The fuse portion 35 of the unit is provided to extend into the passage 12 of the body 11 and a radially extending inner shoulder 36 is provided at the open end of the body to receive a radially extending shoulder 37 of the fuse element 35. Fuse element 35 includes a generally cylindrical extending body portion 38 having a passage 39 therein and terminating at a closed end 40 which closed end operates at a stop for an internal spring or biasing element 41. An inspection aperture 42 is provided in the closed end 40 of the fuse body 38 such that the user or operator may inspect the condition of biasing member 41 without entirely removing the unit from its mounted position. It is only necessary to tilt the unit as in replacement of this fuse element and determine whether the biasing member 41 is being properly held therein by the heat destructable fuse link 43 arranged thereon. As illustrated in FIG. 3 the biasing member 41 is held in its first non-conducting position by a heat destructable element 43 which is arranged within a receiving shoulder 44 of the fuse body 38. Obviously the fuse body 38 must be of a conductive material such that a circuit will be completed between the conductive end 16 of the conductor 15 when the destructable element 43 has been eliminated due to the temperature rise of the engine and has permitted the biasing element 41 to extend to the position illustrated in FIG. 4 which is its extended conducting position.

The use of the unit has been explained previously and the action of the unit should be obvious from the considerations of FIGS. 3 and 4 where in FIG. 3 the eutetic metal or other heat destructable material is maintaining the conductive biasing member 41 in non-conducting position and in FIG. 4 the melting of the eutetic material or heat destructable material has been completed and the biasing member 41 has extended upwardly into conductive position between the connector element and the fuse body 38 which of course as stated is in contact with the head bolt H of the engine. When this circuitary is completed, the spark plug electrical energy will be shorted to the block of the engine and this particular cylinder will not be I firing. Obviously if connected to all of the cylinders of the engine, complete stopping of the engine will occur upon the block of the engine reaching a predetermined dangerous temperature.

Obviously the selected temperature at which the eutetic material will be destroyed is selectable and obviously for water cooled engines a certain temperature will be selected while for an air cooled engine which normally runs at a higher temperature than a water cooled engine a higher eutetic situation will be selected.

With applicants concept it will obviously be impossible to over heat an engine if the device is utilized on all of the cylinders but if utilized on several of the cylinders the operator of the unit will obviously be aware that he is reaching this critical temperature when the misfiring of the engine begins due to shorting out of one or several of the cylinders. This system provides a temperature control system without requiring complicated monitoring devices or the like and without requiring difficult installations for the unit.

What I claim is:

l. A temperature guard device for spark plug fired internal combustion engines including:

a. a nonconductive housing member defining a longitudinal passage therein;

b. a conductor element having a first end carried by said housing and having the second end attachable to a spark plug;

c. means for mounting said housing against the engine block;

d. a fuse block member arranged in said housing to engage the engine block;

e. a conductive biasing element arranged in said fuse block and held in a first non-extending first position and being releasable therefrom to a second conductor element contacting position to complete an electrically conductive circuit from said conductor element to the engine block; and,

f. inspection means in said fuse block member to permit inspection of said conductive biasing element.

2. The structure set forth in claim 1 and said mounting means including a clamping member arranged to permit said device to be removably attached to the engine block.

3. The structure set forth in claim 1 and said fuse block memer being removably received in said housing.

4. The structure set forth in claim 1 and means for holding said conductive biasing element in said first position including heat destructable means.

5. The structure set forth in claim 4 and said heat destructable means including eutectic metallic means.

6. The structure set forth in claim 1 and said conductor element having said first end sealingly attached to said housing. 

1. A temperature guard device for spark plug fired internal combustion engines including: a. a non-conductive housing member defining a longitudinal passage therein; b. a conductor element having a first end carried by said housing and having the second end attachable to a spark plug; c. means for mounting said housing against the engine block; d. a fuse block member arranged in said housing to engage the engine block; e. a conductive biasing element arranged in said fuse block and held in a first non-extending first position and being releasable therefrom to a second conductor element contacting position to complete an electrically conductive circuit from said conductor element to the engine block; and, f. inspection means in said fuse block member to permit inspection of said conductive biasing element.
 2. The structure set forth in claim 1 and said mounting means including a clamping member arranged to permit said device to be removably attached to the engine block.
 3. The structure set forth in claim 1 and said fuse block memer being removably received in said housing.
 4. The structure set forth in claim 1 and means for holding said conductive biasing element in said first position including heat destructable means.
 5. The structure set forth in claim 4 and said heat destructable means including eutectic metallic means.
 6. The structure set forth in claim 1 and said conductor element having said first enD sealingly attached to said housing. 